7 configuration (pressure control), 7 configuration (pressure control – Flowserve 420 IOM User Manual
Page 24
User Instructions - Logix® 420 Series Digital Positioners FCD LGENIM0106-06 12/13
flowserve.com
24
Figure 12: Characterization Curves
Select the appropriate curve as required by the process
design.
Custom - Select Custom for a standard 30:1 linear equal
percent rangability curve. The curve may be customized
point-by point. To modify the Custom curve, use the
ValveSight DTM.
CAUTION: Changing the characterization curve may
cause the valve to move suddenly. Notify proper personnel
that the valve may stroke and if required, make sure the
valve is properly isolated before proceeding.
10.3.7 Configuration (Pressure Control)
The Configuration (Pressure Control) menu allows the user
to change the size of the pressure control window. This
window becomes active when the Valve Stability Switch is
set to “Hi”. The Valve Stability Switch optimizes the
response for valves and actuators with high friction levels.
When
set to “Hi”, it slightly slows the response and will
normally stop limit cycling that can occur on high friction
valves.
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90100
Fi
nal
C
om
m
a
nd
Command Input
Linear
MaxFlo
Linear
MaxFlo
=%
Valdisk
Linear
Valdisk
=%
ShearStre
am Linear
ShearStre
am =%
Table 13: Characteristic Curve Data
Command
Input
Final Command
Characterizatio
n DIP set to
“Linear”
Characterization
DIP set to
“Other”
Linear
MaxFlo
Linear
MaxFlo
=%
Valdisk
Linear
Valdisk
=%
Shear-
Stream
Linear
Shear-
Stream
=%
Custom
(Default)
(Linear =%)
0.0
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
5.0
5.00
6.50
1.00
13.00
4.00
25.00
8.00
0.62
10.0
10.00
11.60
2.00
20.00
6.00
35.00
14.00
1.35
15.0
15.00
16.20
3.00
26.25
7.80
44.00
17.00
2.22
20.0
20.00
20.50
4.40
32.10
9.30
50.20
21.00
3.25
25.0
25.00
24.60
5.80
37.50
11.50
55.50
24.00
4.47
30.0
30.00
28.50
7.40
42.60
14.00
60.20
27.50
5.91
35.0
35.00
32.40
9.30
47.40
16.50
64.30
31.50
7.63
40.0
40.00
36.20
11.20
51.80
19.30
68.00
35.50
9.66
45.0
45.00
40.00
13.50
56.00
22.50
71.50
39.50
12.07
50.0
50.00
43.80
16.10
60.00
26.00
74.70
43.90
14.92
55.0
55.00
47.60
19.10
63.60
30.00
77.70
48.10
18.31
60.0
60.00
51.50
22.40
67.20
34.70
80.50
52.80
22.32
65.0
65.00
55.50
26.20
70.60
39.60
83.20
57.40
27.08
70.0
70.00
59.50
30.60
73.90
45.10
85.90
62.40
32.71
75.0
75.00
63.80
35.70
77.20
51.30
88.40
67.50
39.40
80.0
80.00
68.20
41.70
81.30
57.80
90.80
72.90
47.32
85.0
85.00
73.00
48.90
84.00
64.80
93.20
78.60
56.71
90.0
90.00
78.40
57.70
87.80
72.50
95.50
84.70
67.84
95.0
95.00
85.00
69.20
92.10
81.30
97.80
91.20
81.03
100.0
100.00
100.00
100.00
100.00
100.00
100.00
100.00
100.00
►Configuration
►Pressure Control
►Window